Nuelin SR 250 (Theophylline)

Nuelin general information

What is Nuelin used for?

Nuelin tablets 250mg are used to treat reversible bronchospasm associated with respiratory diseases like asthma, chronic bronchitis, and emphysema; also for prophylaxis to prevent bronchospasm, which is narrowing of the small airways of the lungs or bronchioles.  Bronchospasm causes breathing difficulties with symptoms including, wheezing, shortness of breath, tightness of the chest.  Nuelin tablets 250mg help relieve symptoms of bronchospasm, but is not suitable for acute asthma and will not treat the asthma disease for which you will most likely be taking a regular “preventer” medication such as an inhaled corticosteroid. 

How does Nuelin work?

Nuelin tablets 250mg contain theophylline, a member of the xanthine family with a similar structure and pharmacology to caffeine.  Theophylline in Nuelin tablets 250mg acts as a bronchodilator (relaxes smooth muscle of the bronchioles of the lungs) and pulmonary vasodilator (relaxes smooth muscles in blood vessels of the lungs) that acts directly on the small airways of the lungs (bronchioles).  Contraction of the bands of smooth muscle that surrounds the small bronchiole tubes causes narrowing of the airways in response to an asthma trigger.  Theophylline in Nuelin tablets 250mg is thought to work by inhibiting the enzyme phosphodiesterase, which blocks the breakdown of cAMP (cyclic adenosine monophosphate), an intracellular messenger responsible for signal transduction in many cellular processes.  Build-up of cAMP in smooth muscle cells of the lungs causes smooth muscle contraction and bronchoconstriction (narrowing of the bronchioles).  The action of theophylline in Nuelin tablets 250mg causes bronchial smooth muscle to relax and the airways to widen (bronchodilation).  This reduces bronchospasm (contraction or the airways) and allows the airways to open making it easier to breathe and relieving symptoms of asthma, such as tightness of the chest, wheezing, cough and shortness of breath.  Nuelin tablets 250mg are formulated for slow release and are therefore effective for longer, with maximum effect within 4-6 hours, which last for up to 12 hours.

What does Nuelin contain?

Nuelin tablets 250mg contain the active ingredient theophylline a bronchodilator and vasodilator used to treat reversible bronchospasm.  They also contain guar gum and magnesium stearate.

Treating asthma with Nuelin

Nuelin tablets 250mg contain theophylline, a bronchodilator and vasodilator used to treat and prevent reversible bronchospasm (contraction or the airways) associated with asthma and other respiratory conditions.  Contraction of the bands of smooth muscle that surrounds the small bronchiole tubes of the airways causes narrowing of the airways in response to an asthma trigger.  Theophylline in Nuelin tablets 250mg blocks the build-up of cAMP, an intracellular messenger responsible for signal transduction in many cellular processes, including smooth muscle contraction and bronchoconstriction (narrowing of the bronchioles).  The action of theophylline in Nuelin tablets 250mg causes bronchial smooth muscle to relax and the airways to widen (bronchodilation), which reduces bronchospasm and allows the airways to open making it easier to breathe and relieving symptoms of asthma, such as tightness of the chest, wheezing, cough and shortness of breath. 

What are the side effects of Nuelin?

The most commonly reported side effects when taking Nuelin tablets 250mg include nausea, vomiting, gastric irritation, palpitations, tachycardia, arrhythmias, headache, insomnia and restlessness.

When should Nuelin not be used?

You should not use Nuelin tablets 250mg if you:

• are allergic to theophylline or any ingredients in Nuelin
• are pregnant or are breastfeeding, without discussion with your doctor
• have liver disease
• have acute asthma requiring rapid treatment
• have a condition that affects the clearance of theophylline from the body, including reduced thyroid function, congestive heart failure, acute pulmonary oedema, chronic obstructive pulmonary disease, severe hypoxia, pneumonia, acute febrile episodes and during acute viral infection
• have cardiac arrhythmias, coronary artery disease, unstable angina, cardiomyopathy and severe hypertension due to the effect of theophylline of the heart
• have peptic ulcer or gastro-oesophageal reflux as theophylline increases gastric acid secretion
• are taking medicines that interact with Nuelin, including cimetidine, high dose allopurinol, propranolol, macrolide antibiotics (eg. erythromycin, clarithromycin) quinolone antibiotics (eg. ciprofloxacin and enoxacin), alcohol, oral contraceptives, mexilitene, tacrine, thiabendazole, disulfiram, Interferon alpha and verapamil, tobacco or marijuana smoking, phenobarbitone, phenytoin, carbamazepine and rifampicin, St John's wort, other xanthines

What medications interact with Nuelin?

Several medications interact with Nuelin tablets 250mg and should either not be taken while you are taking Nuelin or only after discussion and instruction from your doctor:

• Drugs that cause a serious reaction with Nuelin: other xanthines
• Drugs that affect Nuelin by increasing serum concentration:  Cimetidine, high dose allopurinol, propranolol, macrolide antibiotics (eg. erythromycin, clarithromycin) quinolone antibiotics (eg. ciprofloxacin and enoxacin), alcohol, oral contraceptives, mexilitene, tacrine, thiabendazole, disulfiram, Interferon alpha and verapamil, tobacco or marijuana smoking, phenobarbitone, phenytoin, carbamazepine and rifampicin, St John's wort
• Drugs that affect Nuelin by decreasing serum concentration:  alcohol, oral contraceptives, mexilitene, tacrine, thiabendazole, disulfiram, Interferon alpha and verapamil, tobacco or marijuana smoking, phenobarbitone, phenytoin, carbamazepine and rifampicin

How should Nuelin be taken?

You should take your Nuelin tablets 250mg swallowed whole with a glass of water with food, one tablet twice daily.  The dose you take and how often depends on your blood levels of theophylline, which your doctor will monitor and your dose may be increased or decreased accordingly.  You should continue to take your Nuelin tablets 250mg for as long as recommended by your doctor.

How long should you take Nuelin?

You should continue to take your Nuelin tablets 250mg for as long as recommended by your doctor.

Missed dose of Nuelin

If you miss a dose of Nuelin tablets 250mg take it as soon as you remember, unless it is time to take the next dose, then skip the missed dose.  Do not take a double dose.

How should Nuelin be stored?

You should store your Nuelin tablets 250mg below 25°C in a cool dry place.